Dragee and method for its manufacture

ABSTRACT

The dragee has a core and a shell adhering to the core, based on sorbitol with an additive of the methyl ester of L-aspartyl-L-phenyl-alanine (aspartame) in the proportion of not more than 0.5% by weight. Also described is a tumbling method of making the shell.

The present invention relates to coated edible products, hereinaftercalled "dragees", comprising a core covered with a shell adhering to thecore and in which at least the shell has a sorbitol base. Coated edibleproducts of the kind cited above are typical of the sweet andpharmaceutical industry.

The use of sorbitol as a sweetening constituent agent in the shell andpossibly in the core in dragees is known in the art, being particularlydesirable for medico-dietetic reasons, and for its weak karyogenicactivity.

The disadvantages arising from the high hygroscopicity of sorbitol arealso well known, and generally render difficult the tumbling operationcarried out in an enrober, which is the basic operation for producingthe shell of the dragee. In fact, by carrying out the tumbling operationwith aqueous sorbitol-based syrups it proved impossible to obtain asmooth and structurally homogeneous shell. In order to overcome thesedisadvantages it was proposed, as described in the Italian PatentApplication No. 68801-A/79 in the name of the applicant, to use sorbitolincluding as an additive a small quantity of sucrose esters.

In cases in which the organoleptic characteristics of the dragee areparticulary important, as in the case of the sweet industry, the use ofsorbitol with small quantities of sucrose ester additives according toknown methods, does not, however, prove wholly satisfactory. As isknown, in fact, a considerable percentage of consumers do not perceive avery pleasant sensation upon contact of the sorbitol with the palate.

It has now been discovered, and this constitutes the basis of thisinvention, that this unpleasant sensation on the consumer's palate canbe eliminated by adding to the sorbitol a quantity of the methyl esterof L-aspartyl-L-phenyl-alanine in a proportion not greater than 0.5% byweight, while at the same time obtaining a smooth and structurallyhomogeneous shell.

Therefore one object of the present invention is a dragee comprising acore covered with a shell adhering to the core and in which at least theshell has a sorbitol base characterised in that the shell comprises aplurality of layers consisting essentially of sorbitol and of the methylester of L-aspartyl-L-phenyl-alanine (aspartame), the latter beingpresent in a proportion of no more than 0.5% by weight referred to theweight of anhydrous sorbitol.

The methyl ester of the L-aspartyl-L-phenyl-alanine, designated in whatfollows by the commonly known term aspartame, is a a commerciallyavailable synthetic sweetener. Nevertheless its use in the production ofdragee has never been suggested up to now. The problems connected withthe low solubility of aspartame in water are in fact known, as well asits instability as a sweetener, particularly in aqueous solution,rendering it hardly suitable for use as a constituent of enrobing syrupsfor tumbling processes.

It has now been discovered that by carrying out the tumbling operationusing an aqueous syrup consisting of aspartame and sorbitol, withinwell-defined concentration limits, it is possible to make dragees withimproved organoleptic characteristics and in which the aspartame in theshell retains its sweetening properties for a practically unlimitedperiod.

A further object of this invention is a method for the preparation of adragee comprising a core and a shell adhering to the core by a tumblingprocess in an enrober, the said method comprising a plurality of stagesof spraying said cores with a sorbitol-based aqueous syrup,characterised in that the said syrup comprises per 100 parts by weightof anhydrous sorbitol, 20 to 60 parts of water and 0.02 to 0.5 parts ofaspartame.

As is known the tumbling operation, which will be described in moredetails below, comprises a plurality of syrup-spraying stages, by meansof which the shell is formed in successive layers. Preferably in themethod according to the invention, the temperature of the syrup ismaintained at 40° to 45° C. in each spraying stage.

It is important that the distribution of the aspartame shall behomogeneous in each single layer formed by sorbitol with aspartameadditive. The preferred concentration of the aspartame in the enrobingsyrup for the tumbling process referred to the anydrous is 0.05 to 0.3%by weight. The sorbitol utlised in the enrobing syrup must be pureanhydrous sorbitol, free from mannitol, since if mannitol is present theresulting shell has unacceptable hygroscopic characteristics. Theenrobing syrup can, however, also contain aromatizers and possiblyflavourings, thickeners, colourings or whiteners of known type.

The cores can be formed from various materials, for example almonds, cutliquorice pieces, caramels of various types, gums, gelatines bonbons, ortablets made by pressing various cooked or agglomerate masses. In thecase in which the core consists of a food substance sweetened withsorbitol or with a sorbitol base, it is preferable for the sorbitol tohave as an additive an aspartame content of not more than 0.5% byweight. It is moreover preferable in these cases for the core to becoated with a thin binding layer for the shell, for example by thedeposition upon the core of a solution of stearic acid in alcohol.

EXAMPLE

The example relates to the preparation of a dragee according to theinvention in which the core also consists of a food compositionincluding sorbitol. For preparing the core, 2 kg of instantisedanhydrous sorbitol were introduced into a mixer. An ethyl alcoholsolution of 2% wt. aspartame was prepared and this solution was sprayedinto the mixture so as to disperse the aspartame uniformly within thesorbitol. The total quantity of alcohol solution of aspartame utilisedwas about 100 g, so that the total quantity of aspartame added to thesorbitol was equal to 0.1% by weight of the sorbitol. Mixing continuedfor a period of about 30 minutes after which the sweetened sorbitol wasdried in a fluid bed with air at 35° C. for one hour. The sweetenedcomposition was then re-introduced into the mixer where it was sprayedwith an emulsion of flavouring and lubricants in ethyl alcohol. In thisphase it is also possible to add to the sorbitol a percentage of thinfilm xylite up to 40% by weight with reference to the sorbitol in orderto render the core more soluble. Following the mixing the substance soproduced was introduced into a press to make the cores of the sweets inthe form of cylindrical pallets with rounded edges having a diameter of5 mm and a length of 11 mm. The cores thus made were coated with analcohol solution of up 25% of stearic acid in ethyl alcohol using aquantity of this solution equal to 0.2% of the weight of the sorbitolcomposition.

A syrup for the tumbling process is prepared to one side, formed by 100parts by weight of pure anhydrous sorbitol free from mannitol, 33 partsby weight of water 0.25 parts by weight of aspartame and 1 partflavourings. Preparation of the syrup was carried out by the addition ofthe aspartame to water at a temperature betwee 40° and 45° C. whilestirring, until complete dissolution. The sorbitol and flavourings werethen introduced into the solution thus produced. For the tumblingoperation an enrobing pan 45 cm diameter was used, rotating about anaxis inclined at 30° to the vertical, at a speed of 47 revolutions perminute. The cores made by the procedure described above were introducedinto the pan. The tumbling process was carried out in 60 cycles andconsisted of the following stages:

(a) spraying for 10 seconds with 45 g of syrup at a temperature of 40°to 45° C.;

(b) a pause for homogenisation for about 30 seconds;

(c) dusting for 5 seconds with about 4-5 g of sorbitol film;

(d) a pause for homogenisation for another 30 seconds;

(e) drying with air at a temperature of about 45°±10° C. for about 3±1minutes;

The aforesaid stages were repeated until a typical final weight equal toabout twice the initial weight of each core was reached. The weight ofthe finished product therefore amounted to about 4 Kg. No difficultieswhatever were encountered in the tumbling process. The individualdragees had a white firm shell with no roughness. It is noted that byusing the process according to the invention it is possible to produce ashell having the desired characteristics even in the absence from theentobing syrup of the sucrose esters suggested by known methods.

Tasting tests were moreover carried by placing before a jury of 10tasters a portion of sweets freshly made by the above descrbed method,and a portion made by the same method and kept for a period of threemonths at ambient temperature. None of the tasters was able to perceivethe albeit minimal difference between the products of the two portions,thus confirming the stability of the aspartame sweetener in the sweetproduct.

I claim:
 1. A dragee comprising a core covered by a shell adhering tothe core, said shell being obtained by spraying a sorbitol-based aqueoussyrup on said core while tumbling said core in an enrober, characterizedin that the shell comprises a plurality of layers consisting essentiallyof sorbitol and of the methyl ester of L-aspartyl-L-phenyl-alanine(aspartame), the latter being present in a proportion of no more than0.02 to 0.3% by weight of anhydrous sorbitol in said shell.
 2. A drageeaccording to claim 1 in which the core consists of a food compositionincluding, sorbitol, characterized in that the sorbitol in the core hasas an additive an aspartame content not greater than 0.5% by weight ofthe anhydrous sorbitol.
 3. A dragee according to claim 2, characterizedin that it includes a binding layer interposed between the shell and thecore and including stearic acid.
 4. A dragee according to claim 1,wherein said layers further comprise one or more additives selected fromthe group consisting of aromatizers, flavourings, thickeners, colouringsand whitenings.
 5. Method for the preparation of a dragee comprising acore and a shell adhering to the core, by tumbling in an enrober, thesaid method incuding a plurality of stages of spraying said cores with asorbitol-based aqueous syrup characterized in that said syrup consistsessentially of anhydrous sorbitol, from 20 to 60 parts of water, and0.02 to 0.3 parts of aspartame referred to 100 parts by weight of saidanhydrous sorbitol.
 6. Method according to claim 5, characterised inthat during the operation of spraying with the enrobing syrup, the syrupis maintained at a temperature of 40° to 45° C.
 7. Method according toclaim 5, wherein said syrup further comprises one or more additivesconsisting of aromatizers, flavourings, thickners, colourings andwhitenings.
 8. Method according to any of claims 5 wherein prior to thetumbling in the enrober said cores are coated with an alcohol solutionof stearic acid.
 9. A dragee comprising a core, the core beingtumble-enrobed by a shell sprayed onto the core and adhering to andcovering the core, said shell being obtained by spraying asorbitol-based aqueous syrup on said core while tumbling said core in anenrober, characterized it that the shell comprises a plurality of layersof a substantially mannitol-free mixture consisting essentially ofsorbitol and of the methyl ester of L-aspartyl-L-phenyl-alanine(aspartame), the latter being present in a proportion of no more than0.02 to 0.3% by weight of anhydrous sorbitol in said shell.